Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
sach van » sach han, sach va, bach van
hieu van » hieu va, thien van, lieu va
van nham » van nam, van nhan, van tham
hanh dai » hanh tai, hanh dao, vanh dai
su sach » so sach, vu sach
nang co » nang cao, nang doc, nang noi
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
nang o » nang ho, nang ro, nang x
cua te » cua tu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach van ((nang o) OR (nang co)) hoi. hieu van nham thuc va hanh dai cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach van ((nang o) OR (nang co)) hoi. hieu van nham thuc va hanh dai cua te".
• Adding a wildcard symbol may retrieve word variants: su sach van ((nang o) OR (nang co)) hoi. hieu van nham thuc va hanh dai cua te*.